Expertise in Gynecological Pathology Impacts Diagnosis of Atypical Glandular Cell Category in Cervical Cytology

The Pap test is effective for detecting squamous neoplasia, but the interpretation of atypical glandular cell (AGC) remains challenging because of its rarity, complex cytologic features, and interobserver variability. Although AGC represents a small proportion of Pap test diagnoses, it often leads to extensive follow-up. This study aimed to assess whether gynecologic pathology expertise improves diagnostic accuracy and reduces unnecessary interventions in AGC interpretation.

A retrospective review of AGC cases diagnosed between 2014 and 2024 at the authors' institution was conducted. Among 107,615 Pap smears, 301 (0.28%) were initially classified as AGC. Of these, 221 had slides available for review, and 184 had adequate histologic follow-up. Cases were re-evaluated by a cytopathologist with additional gynecologic pathology training, blinded to clinical information, and reclassified according to the Bethesda System.

Reclassification identified 62 cases as AGC, 1 as adenocarcinoma in situ, and 4 as adenocarcinoma. The remaining 117 cases were reassigned to other diagnostic categories. The malignancy rate increased from 39.1% to 53.9%, and the positive predictive value for significant histologic findings was 59.7%. Cytology-histology concordance improved from 26.6% to 64.1% ( p = .002).

Gynecologic pathology expertise enhanced the diagnostic accuracy of AGC, improved malignancy detection, and significantly increased cytohistologic correlation. While decreasing sensitivity, it increases positive predictive value of AGC interpretation. These findings highlight the value of specialized training and the need for a specific, criteria-based approach to minimize unnecessary follow-up and optimize patient care.